For developing a composite fabric at various locations, such as laboratories, the usual steps involved are coating, drying and finally pressing to improve adhesion of coating. All the stated steps of coating, drying and pressing are generally performed separately. This increases the operation time, makes the process complex with more involvement of manual efforts thereby leading to less reproducibility due to unavoidable manual errors. In addition, for some applications, these three steps need to be executed in quick succession to avoid the coating formulation from drying up. Thus, there may be a need to design and fabricate a compact coating unit with all these features arranged sequentially such that the entire assembly can be accommodated in the laboratory settings. It may be desirable for the coating assembly to have digital/mechanical control over each of its portion as opposed to the manual control that is most commonly observed in the existing lab coating machines.
Various kinds of industrial knife coating machines are mentioned in different literature reports. However, for all the devices mentioned above, the coating processes are complex requiring several units arranged in series, which eventually occupies a lot of space. Such machines may, therefore, not be suitable for small/lab scale applications.